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Component · physics

Collider

Collision geometry, material, layer and trigger settings.

Fields

kind

ColliderKind
Primitive type or externally cooked shape.
default "box"

One ofboxspherecapsulecylindercookedmodelConvexmodelMesh

center

vec3
Shape center in body-local metres, after visual scale is baked. The body origin remains at Transform/PhysicsPose; rotation also rotates this offset.
default [0,0,0]m

halfExtents

vec3
Box half extents; scale must be baked before physics extraction.
default [0.5,0.5,0.5]m≥ 0.0001shown when kind is box or modelConvex or modelMesh

radius

f32
Sphere, capsule or cylinder radius.
default 0.5m≥ 0.0001shown when kind is sphere or capsule or cylinder

halfHeight

f32
Cylinder half height, excluding the capsule hemispheres.
default 0.5m≥ 0shown when kind is capsule or cylinder

asset

option<asset>
Cooked collision asset (@path#id); resolve into CookedCollider before ticking.
default nullshown when kind is cooked or modelConvex or modelMesh

node

option<string>
Source model node name/index for model-derived geometry; absent uses its default scene.
default nullshown when kind is modelConvex or modelMesh

primitive

option<u32>
Subtree-local primitive for model-derived geometry; absent uses the complete subtree.
default nullshown when kind is modelConvex or modelMesh

layer

u32
Zero selects static/moving defaults from the body; 1..15 select an explicit group.
default 00 – 15

sensor

bool
Report trigger events without a collision response.
default false

friction

f32
Coulomb friction coefficient.
default 0.6≥ 0

restitution

f32
Elasticity: zero is inelastic, one is perfectly elastic.
default 00 – 1

Usage

Every edit is an undoable command: from the CLI as below, or the same JSON from an agent over MCP. See component.add and property.set.

Add it

ara do component.add -p entity=name:Crate -p component=Collider --why "Add Collider"

Set a field

ara do property.set -p entity=name:Crate -p path=Collider.kind -p value="box" --why "Tune Collider"

In a scene document

{
  "Collider": {
    "kind": "box"
  }
}

From C#

/// <summary>Give a crate a grippy surface.</summary>
public static void UseCollider(Entity entity, in Tick tick)
{
    ref var component = ref World.Get<Collider>(entity);
    component.Friction = 0.8f;
}

From C#

Scripts read and write it with Get<Collider>(); see the Collider struct.